Dental hand piece



May 15, 1945. J. WAHLBERG DENTAL HANDPIECE Filed 001,. ll, 1945 Patented Mayra, 1945 .i 2,376,295 N y DENTAL HAND PIECE John Wahlberg, New York, N. Y., assigner to f `Nat Chayes, Rye, N. Y.

Application October 11, 1943, Serial No. 505,870

e claims.` (ci. .e2-26) The invention here disclosed relates to dental` handpieces and more particularly to those parts of themechanism pertaining to the sheath and its method of mounting.

The sheath should be freely rotatable, so as to turn with the fingers grasping it and it should be readily removable from the supporting structure.`

Itis furthermore desirable that any` retaining means for the sheath should be concentric, apply any holding effect equally about thesheath and it should not in any way interfere with the free turning of the sheath.

The purposes of the present invention are to fully answer these several requirements or desired characteristics.

Particularly, it is a purpose of the invention to Aprovide a practical symmetrical form of releasable sheath mounting whichwhile firmly secured during operation of the handpiece'will be quickly and easily releasable at any time andin any normal position of the piece. I

The novelfeatures of the invention by which all the foregoing and other desirable objects are fingers grasping the handon the upper end of the pivotally mounted supporting post t3.

The neadpiece ll, is shown as extended at the opposite side from the sheath supporting sleeve t 8, in the `form` of a cylindrical hub I4, to provide interiorly an elongated bearing extension for the journal portion 9, of the sleeve and exteriorly 'a bearing for the spindle driving pulley I5.

The sheath mounting sleeve is shown as' longitudinally centered in the supporting head by having an annular shoulder lli, at the innerend of the smaller diametered bearing portion 9, in rotatable engagement with the end face of the head and retaining nut l1, screwed on the outer` end of such smaller bearing portion in rotatable engagement with the end of the stationary hub I4. This retainer serves the additional purpose inthe illustration, of confining the pulley l5, in`

rotatable relation on hub I4.

The spindle, indicated at I8, is shown as having a freely rotatable bearing in the smaller diameter `portion of-the sleeve `at I9. This spindle, asin former patent application Ser. No. 487,831, led

` May 19, ,1943, is driven from the pulley through attained are hereinafter set forth, shown by way t of illustration in the accompanying drawing and broadly covered in the claims. V

In the drawing, there is shown but one present practical embodiment of the invention, but it will be recognized that structure may be variously modified and changed as regards this particular disclosure all within the true intent and broad scope of the invention as hereinafterdeflned and claimed.

Fig. 1 in the drawing is a broken longitudinal sectional View of one of the hand pieces, in the assembled operating condition.

Fig. 2 is a broken side elevation, Showing the clutch closing sleeve pulled back to release the sheath and the sheath, carrying with it the spindle, removed from the headstock.

Figs. 3 and 4 are enlarged broken sectional views showing the sheath retaining clutch in the released and holding positions respectively.

Fig. 5 is a broken detail of'a safety lock for the clutch.

In the hand piece illustrated, the sheath l, is removably and rotatably engaged over the larger end portion 8, of a sleeve member having an opposite smaller end portion 9, rotatably engaged in a bearing IU, Within the head H;

This'head forms a part of the supporting structure, being carried by an offset bracket arm a detachable jaw clutch type of coupling, involving clutch teeth 20, on a ange 21, .carried by the pulley, entering in grooves or splines 22, in the end portion of the spindle. Coacting elements of the jaw clutch, preferably have a loose fitting engagement, enabling easy connection and disconnection and providing a self-centering driving relation from the pulley to the spindle. The` driving' flange 2l, is shown inthe form of a sha1- low cup screwed over a shoulder 23, on the outer face of thepulley, clear of and providing a cover over the retaining nut Il.

The sheath retaining clutch is shown in the form of acollar y.24, of a size to pass' over the l smaller bearing portion `of the sleeve and carrying spring fingers 25, at one side, to project longitudinally over the larger sheath supporting portion `of the sleeve. As indicated particularly in Figs. Band 4, these spring fingers are spaced radially from the sleeve a greater distance than the wall thickness of the sheath, so as not to obstruct free rotation of the sheath in its supported position on the sleeve. The collar 24, may be secured in variousways on the sleeve; In

j the illustration, it is shown screwed at 26, over a `shouldered portion at the inner end `of the larger diameter part of the sleeve.

Rotatable holding engagement of the spring fingers with the sheath, is effected in the illustration, by sharply angled inwardly projecting l2, lugs or` teeth 21, on the free ends of such fingers,

angularly extending lug 31, on the midfportion ofthe, same projecting `into position` to stand behind the inner end of the ;ring1-3ll.` `The vlower portionof this catch element is shown as extendeclupward between the two side `portions to form a spring tongue 38,curved atits free end to engage the front of thepostat tworelatively spaced points at 39, both vbelow the pivotal cen-` ter 36. This spring thereby acts to position the catch in the relation shown in Fig. 5, that is,v

e position, but can be released at any time, upon applying pressure to the catch member 35, below the pivotal center 36, to rock the locking lug 3l, below the edge of the ring 30.

While the safety lock is shown in the nature of an accessory or attachment, which may or may not be applied to the stock of the hand piece, it is contemplated that it may be built in as a more` permanent part of the device and if desired' be incorporated in such a way as to be more or less concealed within the body or other portions of the hand piece. s i

What is claimed is:

l. A dental handpiece, comprising a sheath having an external annular groove therein, spring fingers extending from the end of the sheath 1ongitudinally over the samesubstantially to said groove, said ngers having inwardly extending teeth and outwardly extending lugs atthe free ends of the same, said teeth positioned to enter said groove, a ring longitudinally slidable over said spring fingers to contract the same into position with said teeth entered in said groove, said ring having an annular cavity receiving said re1easab1y'ho1ding said stop member intnexririg blocking'position.` i 1 4. A@ dental'handpiece, comprisingxa `headpiece` having a post portion, a :sheath `removablyien, gageable with saidheadpiece, a sheathretaining clutch, including a` clutch retaining ring movable towardsaid post portion, a stop member pivotally mounted onsaid post portion, in position to `prevent clutch releasing movement 'ofs said ring and spring means `for yieldingly holding said stop member in said ring blocking position.

5. A dental handpiece comprising a supporting head having a stationary projecting hub at one side and a bearing extending from the opposite side Aout through said projecting hub, a spindle of lesser diameter than said bearing and insertable into said bearing at said opposite side of the head into position `with the inserted end of the spindle projecting beyond the end of said stationary hub, a sheath rotatably engageable on the head oversaid spindle to rotatably conne said spindle in said bearing and `removable `to permit free withdrawal of the spindle from said inserted lugs in said contracting position of said ring and prevent escape of the ring from the fingers and to limit the extent of closing'movement of the llingers to a point where the inwardly extending I teeth will loosely enter the groove and thereby retain the sheath in relativelyrotatable relation. 2. A dental handpiece, comprising a headpiece,

s asheath removably engaged thereon, a clutch for removably retaining said sheath in position and including a clutchclosing ring shiftable longitudinally of the sheath to effect release of the latter, a safety lock for preventing unintentional releasing movement of said clutch closing ring,

l head having astationary projecting tubular hub said lock including a stop pivotally mounted on holding said stop in the ring-blocking position. 3. A dental handpiece, comprising a headpiece,

including a clutch closing ringshiftable longitudinally of the sheath to effect release of the the headpiece in position to block releasing movement of the ring and spring means for yieldingly` position in the bearing, spring fingers projecting from the head longitudinally over opposite sides of the sheath, said fingers having radially and inwardly projecting retaining lugs at the free ends of the same and the sheath having a continuous annular` groove to rotatably receive said retain- `ing lugs, said iingers being spring biased in an opening direction to clear said retaining lugs of saidxannular groove, a ring longitudinally `slidable over said spring lingers and having an annular internal cam surface to contract said spring fingers 'far enough for the retaining lugs on the ends of the same to loosely enter in said annular groove and thereby rotatably coni-lne the sheath on the head, a drive pulley` surrounding and journalled on the stationary projecting hub,`

means rotatably confining said pulley supported in said journalled position on the stationary hub independently of the spindle and whereby said spindle may be freely inserted into its bearing or be withdrawn from the bearing and removed from the head without disturbing thevpulley rotatably supported on the stationary hub of the head and -coacting endwise engageable clutch elements on the pulley and projecting end portion of the inserted spindle .freely engageable and disengageable inthe longitudinal` insertion of the spindle in and removal of the same from said bearing for effecting automatic coupling of the spindle to the pulley and uncoupling ofthe spindle from the pulley by the simple act of inserting the spindle in or removing 'it fromI the bearing in the head.

6. A dental handpiece comprising a supporting at one side and a bearing passage extending from the opposite side of the head concentrically through said tubular projecting hub, a bearing sleeve journalled in said bearing passage and extending through said stationary projecting hub, means engaged with the` extended end of said bearing sleeve and with the end of said stationary hub for rotatablyconiining said bearing sleeve in the head, said bearing sleeve having a supporting portion projecting from said opposite'side of theA y head, a sheathengaged oversaid supporting porlatter, a safety lock for preventing unintentional j ported on the headpiece in position to block clutch releasing movement of said ring and means for tion of the bearing sleeve, means on said supporting portion for releasably coniining said sheath in supported position, said bearing sleeve having a concentric bearing passage therethrough, a spindle journalled in said last mentioned bearing passage and rotatably conned therein by said e supported on; the stationary wholly indet- 10 pendentliof the removable spindle; and aafnge oarrid by the outer side` of the pulley extending radiallyinwardIy over the adjoining end ofY the statief-1'aryy hub and 'having a radially extending clutch element projectinginwardly beyond the diameter of the bearing passage in whichthe spindle is journall'ed and cooperable with the v clutchf elementv on the; projecting endl of he spindle.

J OI-IN WHLBERG. 

